tsan_mutexset.h revision 2d1fdb26e458c4ddc04155c1d421bced3ba90cd0 
1//===-- tsan_mutexset.h -----------------------------------------*- C++ -*-===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This file is a part of ThreadSanitizer (TSan), a race detector.
11//
12// MutexSet holds the set of mutexes currently held by a thread.
13//===----------------------------------------------------------------------===//
14#ifndef TSAN_MUTEXSET_H
15#define TSAN_MUTEXSET_H
16
17#include "tsan_defs.h"
18
19namespace __tsan {
20
21class MutexSet {
22 public:
23  // Holds limited number of mutexes.
24  // The oldest mutexes are discarded on overflow.
25  static const uptr kMaxSize = 16;
26  struct Desc {
27    u64 id;
28    u64 epoch;
29    int count;
30    bool write;
31  };
32
33  MutexSet();
34  // The 'id' is obtained from SyncVar::GetId().
35  void Add(u64 id, bool write, u64 epoch);
36  void Del(u64 id, bool write);
37  void Remove(u64 id);  // Removes the mutex completely (if it's destroyed).
38  uptr Size() const;
39  Desc Get(uptr i) const;
40
41  void operator=(const MutexSet &other) {
42    internal_memcpy(this, &other, sizeof(*this));
43  }
44
45 private:
46#ifndef TSAN_GO
47  uptr size_;
48  Desc descs_[kMaxSize];
49#endif
50
51  void RemovePos(uptr i);
52  MutexSet(const MutexSet&);
53};
54
55// Go does not have mutexes, so do not spend memory and time.
56// (Go sync.Mutex is actually a semaphore -- can be unlocked
57// in different goroutine).
58#ifdef TSAN_GO
59MutexSet::MutexSet() {}
60void MutexSet::Add(u64 id, bool write, u64 epoch) {}
61void MutexSet::Del(u64 id, bool write) {}
62void MutexSet::Remove(u64 id) {}
63void MutexSet::RemovePos(uptr i) {}
64uptr MutexSet::Size() const { return 0; }
65MutexSet::Desc MutexSet::Get(uptr i) const { return Desc(); }
66#endif
67
68}  // namespace __tsan
69
70#endif  // TSAN_MUTEXSET_H
71